Investigación

 

The laser-backscattering equations and their application to the study of the atmospheric structure

 

R. Castrejón-García¹, J. R. Varela², J. R. Castrejón-Pita³, A. Morales⁴

 

¹ Instituto de Investigaciones Eléctricas Av. Reforma 113, Col. Palmira, 62490 Temixco, Mor., México. e-mail: rcg@iie.org.mx

² Universidad Autónoma Metropolitana-Iztapalapa Av. Michoacán y la Purísima, Col. Vicentina, 09340, México, D. F. e-mail: jrvh@xanum.uam.mx

³ Centro de Investigación en Energía, Universidad Nacional Autónoma de México Apdo. Post. 34, Temixco, Mor., 62580, México. e-mail: jrcp@cie.unam.mx

⁴ Centro de Ciencias Fósicas, Universidad Nacional Autónoma de México Apdo. Post. 48-3, Cuernavaca, Mor., 62251, México. e-mail: mori@fis.unam.mx

 

Recibido el 19 de marzo de 2002.
Aceptado el 8 de julio de 2002.

 

Abstract

In this work a method for interpreting backscattering signals acquired by a lidar is described. The method is based on the elastic scattering of laser radiation due to gases and particles suspended in the atmosphere (bulk effects). We propose a space-time diagram which helps to evaluate the arguments of the equation that serves to calculate the lidar signal in terms of the backscattering coefficient. We describe how the system detects gradients on this coefficient, along the laser optical path. To illustrate the method, we present some typical lidar results obtained in the neighborhood of Mexico City.

Keywords: Lidar; atmospheric light-backscattering; laser remote sensing.

 

Resumen

En este trabajo se describe el desarrollo de un método que sirve para interpretar las seriales de retrodispersión adquiridas por un sistema similar al radar conocido como lidar. El método se basa en la dispersión elástica de radiación laser, producida por gases y partículas suspendidas en la atmósfera (efecto global). Presentamos un diagrama de espacio-tiempo que ayuda a evaluar los argumentos de la ecuación que permite calcular la señal lidar en términos del coeficiente de retrodispersión. Explicamos también, el procedimiento que permite detectar los gradientes de ese coeficiente a lo largo de la trayectoria óptica láser. Se muestran algunos resultados de la aplicación del método en sitios vecinos a la Ciudad de México.

Descriptores: Lidar; retrodispersión atmosférica de luz; detección remota con láser.

 

PACS: 42.68.Wt

 

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Acknowledgements

R. C. G. expresses his gratitude to the Universidad Autónoma Metropolitana-Iztapalapa for providing him its intellectual atmosphere. This research was supported by the Consejo Nacional de Ciencia y Tecnología and the Instituto de Investigaciones Eléctricas and the DGAPA-UNAM (IN101100), México.

 

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